Wireless communication systems generally include a plurality of communication devices, such as mobile or portable radio devices that are located in multiple sites. Each site may include a set of base stations or repeaters for communicating information such as voice, data, control, and network management traffic between the communication devices and each other. The devices may be further logically divided into various subgroups, known as talkgroups, where each talkgroup can include a number of subscriber radio devices that participate in a group or dispatch call. Such communication systems also support group data messages, where a group data message sent by the subscriber radio device is received by other members of the group via communication links established between multiple end points, such as repeaters and dispatch consoles. Radio devices may use group data to deliver over the air information including firmware, parameters, keys, images, talkgroup management parameters, and the like.
Some wireless communication systems employing group data communication support only unconfirmed delivery of group data. Applications using group data, however, may need to know the success or failure of delivery. One existing method to provide such confirmation information is to build a solution at the application layer that allows applications to track the success or failure of a delivery of group data. However, providing confirmation mechanisms at the application layer reduces the effectiveness of group data. One method for providing confirmation is to have the receiving radio devices provide the confirmations by randomly delaying their acknowledgments of delivery, where the random delay is large enough to reduce the probability of collisions to an acceptable value. The main disadvantage of random delay is that it reduces the overall throughput of the group data. Further, the random delay may become worse if systems employ selective automatic repeat-request protocol (selective ARQ) for delivery and acknowledgment of group data, where selective ARQ is a specific instance of the ARQ protocol used for communications. Where long packets are used, the reliability of delivery can further decrease without the implementation of selective ARQ. For example, if the reliability of the delivery of a burst or block of data (12 bytes) is 99%, then for 32 bursts (384 bytes), the reliability reduces to 72%.
Accordingly, there is a need for an improved solution that provides group data delivery confirmation.
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The method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.